Promises of Inheritance: Applying Estoppel in Will Disputes
Wills and Estates: 28 November 2025
Author: Tracey Bannister - Our People
The amendments made to the categories of people eligible to make family provision claims under Part IV of the Administration and Probate Act 1958 were made over a decade ago and were intended to reduce the amount of family provision claims by reducing the categories of people who were eligible to apply.
Whether or not you are eligible to make a family provision claim, other types of claims should be considered before embarking on expensive litigation, which may ultimately achieve a better outcome than a family provision claim depending on the specific facts of your matter. It is important to seek appropriate legal advice in relation to your matter.
One of the many other types of claims in estate litigation is a claim for equitable estoppel. Equitable estoppel is effectively a principle of equity which prevents a party from departing from a previous representation or promise, where another party has relied upon that particular representation or promise and has suffered detriment as a result.
Generally, equitable estoppel can be:
- proprietary estoppel; and
- promissory estoppel.
Proprietary estoppel concerns representations (or “promises”) that relate to proprietary interests. Proprietary estoppel can be categorised as either estoppel by encouragement, or estoppel by acquiescence.
Promissory estoppel concerns representations (or “promises”) that relate to non-proprietary interests. Usually this is used in defence of a claim, rather than being a claim in its own right. It is where a party is prevented from breaking promises to re
The elements that must be satisfied to establish equitable estoppel are:
- The plaintiff must have assumed or expected that a particular legal relationship existed or would exist between the plaintiff and the defendant (or the deceased) and the assumption or expectation must include the belief that the defendant/deceased would not be able to withdraw from the relationship;
- The deceased/defendant must have induced the plaintiff to adopt the assumption or expectation;
- The plaintiff must have acted in reliance on the assumption or expectation;
- The deceased/defendant intended or knew that the plaintiff had relied on the assumption or expectation;
- The plaintiff acted on the assumption or expectation to their detriment;
- The deceased/defendant has failed to act to avoid that detriment.[1]
Proprietary estoppel
One of the more recent cases concerning proprietary estoppel is the decision of the High Court of Australia in Kramer v Stone [2024] HCA 48.
Dame Leonie Kramer made her final Will in 2011, whereby she left a rural property to one of her daughters, Hilary Kramer.
David Stone had farmed the property since 1975 under an oral share farming agreement he had with Dr Harry Kramer, Dame Leonie’s husband who was the proprietor of the rural property at that time. The agreement was an oral agreement for a profit share. In the 1980’s, Dr Harry Kramer made representations to Mr Stone that he would be leaving the rural property to his wife, but that she would leave the property to Mr Stone in her Will.
Dame Leonie confirmed that she and her husband had agreed that Mr Stone would receive the rural property upon her death, along with a sum of money.
Mr Stone relied on these representations to his detriment. He continued to work on the farm pursuant to the agreement for some 23 years and in doing so, only received an irregular and meagre income and poor accommodation.
Dame Leonie died in 2016, and did not leave the rural property to Mr Stone as promised.
At trial, the Supreme Court of New South Wales held that the circumstances gave rise to an estoppel against the estate, and required the title to the rural property to be held on trust for Mr Stone.
The executors were not happy with the decision, and appeals to the Court of Appeal, and ultimately to the High Court of Australia. The appellant executors argued that proprietary estoppel by encouragement had a necessary element that the promisor further encouraged or had actual knowledge of the detrimental reliance after making the promise.
The High Court dismissed the appeal (by majority of Gageler CJ, Gordon, Edelman and Beech-Jones JJ, with Gleeson J dissenting), and reaffirmed the elements of proprietary estoppel:
- There must be a “clear and unequivocal” promise made by the promisor to the promise;
- A reasonable person in the promisor’s position must have expected or intended or the promisor did expect or intend that the promise would rely on such promise through an act, omission, or course of conduct;
- The promisee relied upon the promise through an act (or omission) in the general manner that would have been expected, which the promise would not have done but for the promise; and
- As a consequence, the promise suffered or will suffer detriment in the even the promise is not fulfilled.
Notably, the High Court held that neither further encouragement nor actual knowledge of the detrimental reliance was required, and that it was sufficient that Dame Leonie knew that Mr Stone would rely on her promise by continuing to share farm.
Promissory estoppel
One of the more recent cases concerning promissory estoppel is the decision of the Supreme Court of Victoria in Tran v Hoang [2022] VSCA 194.
In this case, a father (Khiem Tran) and two of his sons (Tony Khoa Tran and Anthony Khang Tran) entered into a Deed dated 6 June 2017. Pursuant to the Deed, the father agreed to give Tony $300,000, Anthony agreed to vacate a house owned by the father, and Tony agreed to repay $300,000 to the father if Anthony did not vacate the house by a specified date. The father died about a year after signing the Deed, and without having paid Tony $300,000 despite Anthony having vacated the house.
At trial, Tony failed in his action against his father’s estate to recover the $300,000.
On appeal, this was overturned and it was held that the Deed created an immediately binding obligation for the father to pay Tony $300,000 in 2017, and the intervention of equity was required to complete the gift. The father made a binding promise, and breached that promise to the detriment of Tony which entitled him to damages.
The proof of loss required no more than prove that a promise had been made to pay a fixed, ascertained sum of money by a stipulated date, the date had passed and no payment had been made. Tony was not required to prove steps he had taken to mitigate the loss, or consider whether the loss arose from Tony’s reliance on the promise as the loss was the amount not paid.
Summary
Many estate disputes involve claims that the deceased made certain promises in relation to inheritance of their assets. Often the scenario may arise in the case of a family farm, where a child works on their parents' farm for years for little or no remuneration, in reliance upon promises made by the parents that that child would eventually inherit the farm.
It is important in estate litigation to think outside the "Part IV/family provision box. These cases are examples of how a claimant may be successful in obtaining a share of a deceased's asset based upon promises, despite the asset not forming part of the estate at the date of death.
[1] FJ & PN Curran Pty Ltd [2019] VSCA 236, at 253; Walton Stores Ltd v Maher [1988] 164 CLR 387, at 423.